Cas9-induced DSB. Indel (insertion/deletion) creat- ed by NHEJ of DSB introduces premature stop codon. Knockouts Use non-homologous end joining (NHEJ) to inactivate genes by frameshift mutation. 2,3 • Rapidly generate knockout cell lines and animals. • Analyze loss of function for single-gene knockout. • Study combinatorial effects, pathway redundancy, and epistatic relationships via multigene knockout. • Investigate the role of genes in cell processes, disease models, and drug response. Genetic engineering has been boosted by the discovery and characterization of CRIPSR-associated Cas9 RNA-guided endonuclease. 1 This technology enables rapid genetic perturbation and manipulation, as well as genome-wide functional screening. With broad basic science and translational applications, this technology is driving innovative life science and medical research. Transcriptional Interference or Activation Target genes to repress expression with CRISPR interference (CRISPRi) or activate expression with CRISPR activation (CRISPRa). 12–14 • Study the effect of gene knockdown or activation in a reversible system. • Target multiple genes simultaneously to study gene networks and combinatorial effects. PAM sgRNA 1. M. Jinek et al., “A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity,” Science, 337(6096):816-821, 2012. 2. L. Cong et al., “Multiplex genome engineering using CRISPR/Cas systems,” Science, 339(6121):819-823, 2013. 3. P. Mali et al., “RNA-guided human genome engineering via Cas9,” Science, 339(6121):823-826, 2013. 4. A. Park et al., “CRISPR/Cas9 allows efficient and com- plete knock-in of a destabilization domain-tagged essen- tial protein in a human cell line, allowing rapid knock- down of protein function,” PLOS ONE, 9(4): e95101, 2014. 5. R.J. Platt et al., “CRISPR-Cas9 knockin mice for genome editing and cancer modeling,” Cell, 159(2):440-455, 2014. 6. M. Ratz et al., “CRISPR/Cas9-mediated endogenous pro- tein tagging for RESOLFT super-resolution microscopy of living human cells,” Sci Rep, 5:9592, 2015. 7. H. Yang et al., “One-step generation of mice carrying re- porter and conditional alleles by CRISPR/Cas-mediated genome engineering,” Cell, 154(6): 1370-1379, 2013. 8. T. Fujita, H. Fujii, “Efficient isolation of specific genomic regions and identification of associated proteins by engineered DNA-binding molecule-mediated chromatin immunoprecipitation (enChIP) using CRISPR”, Biochem Biophys Res Commun, 439(1):132-136, 2013. 9. B. Chen et al., “Dynamic imaging of genomic loci in living human cells by an optimized CRISPR/Cas system,” Cell, 155(7):1479-1491, 2013. 10. P.S. Choi, M. Meyerson, “Targeted genomic rearrange- ments using CRISPR/Cas technology,” Nat Commun, 5:3728, 2014 11. L.S. Qi et al., “Repurposing CRISPR as an RNA-guided platform for sequence-specific control of gene expres- sion,” Cell, 152(5):1173-1183, 2013. 12. S. Konermann et al., “Genome-scale transcriptional acti- vation by an engineered CRISPR-Cas9 complex,” Nature, 517(7536):583-588, 2015. 13. L.A. Gilbert et al., “Genome-scale CRISPR-mediated control of gene repression and activation,” Cell, 159(3):647-661, 2014. 14. T. Wang et al., “Genetic screens in human cells using the CRISPR-Cas9 system,” Science, 343(6166):80-84, 2014. 15. S. Chen et al., “Genome-wide CRISPR screen in a mouse model of tumor growth and metastasis,” Cell, 160(6):1246-1260, 2015. 16. O. Shalem et al., “Genome-scale CRISPR-Cas9 knockout screening in human cells,” Science, 343(6166):84-87, 2014. Use of CRISPR/Cas technology to tag TERF1 with Tur- boGFP. Endogenous TERF1 was tagged with TurboGFP at the N-terminus. Cells were fixed in paraformalde- hyde and stained with DAPI. Microscopy images show a dotted TERF1 pattern, indicative of TERF1 binding to telomeres. Tagging Use HDR to introduce an epitope tag or fluo- rescent marker at a targeted locus or visualize genomic DNA with a tagged-Cas9 mutant. • Fuse endogenous genes or genomic loci to fluorescent proteins. 6 • Introduce conditional alleles, e.g. LoxP or FRT. 7 • Epitope tag (e.g. His or FLAG) targeted genom- ic sequence to enable downstream analysis. 8 • Visualize genomic elements in living cells via sgRNA tiling. 9 NHEJ Indel Stop Codon Knockins Introduce specific nucleotide modifications to genomic DNA via homology-directed repair (HDR). 4,5 • Rapidly generate cell lines and animals. • Target gene expression and noncoding DNA elements (enhancers, promoters, etc.). • Introduce gain-of-function and loss-of- function mutations in endogenous genes to study the impact of SNPs or somatic mutations on gene function. • Simultaneously target mutations to multiple genomic regions. Nucleotide Modification HDR Repair Template Use of CRISPR/Cas technology to engineer the CD74-ROS1 translocation. HEK 293T cells were treated with Cas9 along with two guide RNAs that introduce two DNA double-strand breaks on chromosomes 5 and 6. The resulting clonal cell line bears a balanced translocation that can be visualized by spectral karyotyping. 10 Chromosomal rearrangements Use two double-stranded breaks to delete intervening genomic regions. 11 • Study complete gene knockouts. • Investigate the function of noncoding regulatory elements. • Analyze haploinsufficiency with monoallelic deletion clones. • Rearrangements include deletions, translocations, and other modifications. Chr 5 gRNA2 CD74 Chr 6 ROS1 gRNA1 Parental CD74-ROS1 Chr 6 CD74-ROS1 Chr 5 ROS1-CD74 Genetic Screening Systematically identify genes involved in biological processes via high-throughput CRISPR screens. • Genome-wide gene activation and repres- sion screening. 13,14 • Systematically identify genes involved in biological processes. 15 • Screen to identify genes involved in disease models and drug response. 16,17 CRISPR technology is transforming life science research gene repression (CRISPRi) gene activation (CRISPRa) X X TERF1-TurboGFP Cell 1 References: Cas9-induced DSB in presence of repair template. Targeted nucleotide modification is introduced to ge- nomic DNA by HDR. DAPI Cell 1 CRISPRi: Inactive Cas9 (dCas9) fused to a transcrip- tional repressor is targeted to inhibit gene expression. CRISPRa: dCas9 fused to a transcriptional activator is targeted to activate gene expression. Custom Publishing from Sponsored by Cas9 Contact Horizon for help with any of these CRISPR applications. www.horizondiscovery.com